Spades is a 4-player partnership game played with a standard deck of 52 cards.
The objective is to win the most points by taking "tricks" during the game.
The first team to reach either 100, 200, or 500 points (depending on game settings) wins. If both teams reach the winning points total on the same deal, the team with the higher score wins. If one team reaches -200 (or less) the game ends and the team with the highest score at that point wins.
At the start of the game, all 52 cards are dealt out. Each partnership then bids the number of tricks they expect to take during the hand. Each player makes their bid in turn.
A player may bid any number of tricks from 1 to 13, or may bid "nil," which means they undertake not to win any tricks during that hand. The bid made by the partner of the nil bidder becomes the total bid for the partnership.
In each suit, cards rank from highest to lowest: A, K, Q, J, 10, 9, 8, 7, 6, 5, 4, 3, 2. Spades are always trump, meaning any spade will beat any non-spade card, regardless of rank.
The dealer leads the first trick. The winner of each trick leads to the next trick. Spades cannot be led until they are "broken" by someone playing a spade on a trick. However, a player who only has spades may lead with them.
Since spades are trump, the highest spade played on any trick wins. If no spades are played, the highest card of the suit led wins the trick.
If a partnership takes at least as many tricks as their bid, they earn 10 points for each trick bid plus 1 point for each additional trick (bags) taken. Every 10 extra tricks per game results in a deduction of 100 points.
For example, if a team gets 9 bags in one round and 9 bags in the next, they lose 100 points. They now have 18 bags total for the game. The next two bags they get will result in another 100 point deduction.
A team failing to make their bid loses 10 points for each trick bid.
A player who bids nil and takes no tricks earns their partnership a bonus of 100 points. If a nil bidder takes at least one trick, their partnership loses 100 points. Additionally, normal scoring applies based on bids and tricks taken.
If a team bids to take all 13 tricks during a round and they do so successfully, they'll be rewarded 200 extra points (this is also known as a Boston). This can't be done if the opposing team has bid double nil.
Try to count the tricks you can be fairly sure that you can take:
Since you score more points for bidding and taking more, you should at minimum bid the total of your fairly sure tricks. If you have good flexibility, you can stop right there and try to make your bid exactly without straining.
If you have few low cards but many tens, jacks, and queens, add at least a trick to your sure tricks; this will give you a higher score if you're successful, while keeping your overtricks to a minimum if the hand is underbid (that is, if the total of the bids is less than 13, making players reluctant to win tricks even when they can)
At the start of play, consider whether a hand is underbid or overbid--that is, whether the total of tricks is less than or greater than 13. On underbid hands, players should generally try to avoid taking anything but their certain tricks, while on overbid hands they should try to take whatever they can get.
If a player wins a trick with a low card early in the hand, that player is probably no longer on track to make his or her bid exactly. The same is true of a player whose ace is trumped on the first round a suit is led. If your partner is one of those who has met with the unexpected, look for an opportunity to make up the difference by winning or losing a trick you didn't plan to.
Contracting to take no tricks is a risky strategy, and cannot be reasonably tried without a weak spade holding and low cards in all suits. If partner has already bid a high number, though, a player may succeed at a nil bid without such a perfect hand, since partner's ability to win tricks offers some protection.